Valentine Tallon born c1799 Dungarvan Waterford

My BIG Irish Brick Wall line is the Tallons from Dungarvan Waterford / Mullinahack Dublin.

I believe the following:

Valentine Tallon born c1799
Married Frances Akehurst in 1837 in Sussex England (He was a Coastguard)
(no idea when he went to Sussex or if any other family went with him)

I believe his parents are
Valentine Tallon c1771 of Waterford  and Mary Ryves or Reeves c1775 (they married 1796 in Waterford)

I believe his Grandparents are

Valentine Tallon c1736 of Mullinahack Dublin and Elizabeth Geoghagan c1740 (married 1768 Mullinahack Dublin)

Tallon changes in census and certificates as Tallen Tallon Tallend and Tallent

I have no firm evidence of any of these births.
I beleive Dominick Tallon(born 1796)  is a brother to my Vakentine- Domonick appears to have been a prominant Catholic and a landlord - he lived at Laken Lodge Abbeyside Dungarvan.

I found bancrupcy details for a Valentine Tallon in Dublin in 1778/79 and a foreclosure on a property notice in Waterford 1792  So I suspect the Tallons moved from Dublin to Waterford between 1779 and 1792.

Any help greatly received. Im planning a visit this summer to Waterford and Dublin to do some on feet on the grounds research but would be good to go with some evidence of what churches or graveyards to be looking at.

Years ago I found an online article talking abut the post mistress in Dungarvan over hearing a Valentine Tallon making plans to do with the Uprising in 1798, cant find that article now.

Many thanks for any help available with this family.
Helen